Techniques have been developed for controlling hybridization between oligonucleotides with complementary structures by an external stimulus. If hybridization control could be achieved, it could contribute to more precise gene detection, identification and assay, and to the development of molecular devices and molecular machines using oligonucleotides for example. pH changes, temperature changes, light irradiation and the like are used as external stimuli for controlling hybridization.
Patent Documents 1-3 describe techniques for reversibly hybridizing an oligonucleotide using light irradiation. This oligonucleotide has a residue containing an organic group such as an azobenzene or azobenzene derivative that can undergo an isomerization reaction between cis- and trans-forms in response to light irradiation. In Patent Documents 1-3, light in the ultraviolet range of less than 400 nm must be used for one or both of the cis-trans isomerization reaction and the trans-cis isomerization reaction.